Pronunciation: (hī'u-sinth),[key] —n. 1. a bulbous plant, Hyacinthus orientalis, of the lily family, widely cultivated for its cylindrical cluster of fragrant flowers in a variety of colors.
2. any of various similar or related plants, as the grape hyacinth or the water hyacinth.
3. a plant fabled to have sprung from the blood of Hyacinthus and variously identified as iris, gladiolus, larkspur, etc.
4. Mineral.a reddish-orange zircon.
5. a gem of the ancients, held to be the amethyst or sapphire. Also called jacinth for defs. 3–5.